Mark IV Combo - rattling?

[thindave]

Hi all, new to the forum (been lurking a little while...). I have a Mark IV short combo - bubinga & wicker which I bought new back in 92 or 93 which I've just started playing again after a few years of sitting in my closet.

Anyway, when I first powered it up, it played for a bit until the fuse blew. I checked the tubes and saw one that glowing pretty brightly right after powering it up, so I swapped it and another out for two new mesa el34's I picked up in my local shop.

I'm now noticing something like a high pitch rattling noise when playing the R2 or lead channel. I'm going to bring it in to get it a once-over, but I figured I would check here first in case anything jumped out an anybody...

Also, thanks for the great forum - lots of good info here!

Dave

 

[srf399]

Sounds like a preamp tube... try swaping the preamp tubes for the R2 channel. V2 I think

 

[thindave]

Thanks, I was thinking about a full re-tube anyway. I know a lot of folks recommend Eurotubes - any other suggestions?

 

[AMG1]

This might sound silly but.... are you sure its the amp?

My MKIV can rattle a room pretty good.

 

[thindave]

That's funny you mention it because I did have it happen once with my Bose PAS1 - I was like "This thing is borked! Whenever I play an F#, it's rattling like crazy..." Until I noticed that it was just shaking the hell out of the pictures on my wall...

I'm pretty sure it's the amp as I listened closely at the open back - I think after 13 years it's time to change the tubes out anyway...

Thanks!

 

[AMG1]

Oh yeah I'd say your due . Tubes dont last forever.

It just reminded me of a door jam that was making noise. I could'nt figure it out until I just happened to lean against it and suddenly I found my noise.

 

[thindave]

Well, I followed the recommendations of others here on the forum and ordered a 6V6 replacement set from Bob @ Eurotubes and all I can say is wow. Great warm, creamy gain at reasonable volumes - I highly recommend them!

 

[Brewski]

Did the replacement tubes make the rattling stop?

 

[thindave]

Yeah, there must've been a bad one in the bunch - thanks to all for the help and suggestions...

 

[brianf]

A little trick for finding out which tube is rattling is to have a friend play the note or notes that cause the rattle. Put on an oven mitt and grab the tubes one by one. Rattle stops and you found the tube. I find that EL34's will be more prone to rattle than 6L6.


brianf

 

[Nocki]

My neighbour used to knock on the walls when playing. Sometimes when i'm playing powerchords and low stuf I stop because I think shes at it again. when i stop the sounds stop. I had this for 2 months when I found out it was the Low notes reaching the wall and coming back from it! It really sounds like someone banging the walls!!!!

 

[Boogiebabies]

I use an Auralex Gramma riser for all of my combo's. Otherwise, they are sympathetic with the room on certain notes and it shakes the whole room.

 

[HappyStrat]

My Mark IV combo used to rattle too.

This went on for several months & I could never figure it out until one day the "Clue Bird" landed on my shoulder.

It was the 4 removable casters that I had stored away in the back. DUH.....

 

[jukesgtr]

I went and got new tubes for my Peavey C30 because I thought one of the power tubes was bad....changed all tubes and the trouble was still there. Notices the bad/rattling sound (on certain notes played on lower register that REALLY sounded as a tube problem) came from a one scratchy pot in the amp, vibrating i.e. contact/no-contact when playing!! Sprayed all pots with contact cleaner that solved the problem.

PS: I still needed spare tubes for the amp so these new JJs will not be wasted!